I. Field of the Invention
This invention relates generally to apparatus for performing transluminal angioplasty and related procedures, and more particularly to an improved Y-connector or hub for attachment to the proximal end of a guide catheter for limiting movement of a guidewire used in the placement of the working catheter within the vascular system.
II. Discussion of the Prior Art
In carrying out various surgical procedures, such as coronary artery balloon angioplasty, a balloon-tipped catheter must be routed through the vascular system and across the stenotic lesion so that when the balloon tip on the working catheter is inflated, the partially occluded coronary artery will be spread to a patent condition. In carrying out this procedure, an incision is usually made in the patient's leg to gain access to the femoral artery and a relatively large diameter guiding catheter is inserted through an introducer and routed through the vascular system until its distal end approaches the coronary ostium.
Following the insertion of the guide catheter, a relatively small diameter flexible guidewire is inserted through the proximal end of the guide catheter and advanced through it until the distal end of the guidewire exits the distal end of the guide catheter. By appropriately manipulating the proximal end portion of the guidewire, the physician is able to steer the guidewire into the coronary artery to be treated. Once the guidewire has been advanced so that its distal end is downstream of the lesion to be treated, a balloon catheter, such as described in U.S. patent application Ser. No. 893,558, filed July 14, 1986, and entitled DILATION CATHETER is fitted over the guidewire in the manner described in that application and then fed through the guide catheter. In that the distal end portion of the balloon-tipped catheter is captured onto the guidewire, as the balloon catheter exits the guide catheter, it follows the guidewire until the balloon is made to bridge the stenotic lesion to be treated.
The angioplasty procedure often dictates that working catheters having balloons of differing shapes and diameters be utilized successively. Thus, it is frequently required that a first balloon catheter be removed and replaced sequentially with one or more other working catheters. It is important that the guidewire remain in place until the procedure is completed, thus avoiding the necessity of repositioning the guidewire. When it is considered that several different working catheters are passed back and forth along the guidewire during the course of a procedure, it has required that the physician or a nursing attendant be able to readily grasp and hold the proximal ends of both the guidewire and guide catheter as the working catheters are repositioned. This is an impediment to the physician's ability to effectively manipulate the working catheter in that both hands are occupied with holding the guidewire and guide catheter.
All of the foregoing is by way of background for a better understanding of the construction and use of the present invention. In accordance with the present invention, the conventional Y-connector or hub used on the distal end of the guide catheter is replaced by a hub having an arm extending laterally and proximally from an exterior side surface thereof. This arm extends slightly beyond the proximal end of the hub body and on the free end of the arm is a releasible clamp which may be used to grip the guidewire and thereby hold it fixed relative to the guide catheter. Because of this clamping arrangement, there is no relative movement of the guidewire within the guide catheter and, hence, the possibility that the guidewire is inadvertently retracted is greatly reduced. Moreover, the lateral displacement of the proximal ends of the guidewire and working catheter provided by the arm maintains the guidewire out of the way when manipulating the working catheter.